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这是一个创建于 2881 天前的主题，其中的信息可能已经有所发展或是发生改变。
python 中 id([1]) == id([2]) 为 True,这是为啥啊
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czheo 2017-01-21 11:28:23 +08:00  1
性能优化，内部把 list 重用了吧。
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imn1 2017-01-21 11:31:24 +08:00
id([1]) is id([2])
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czheo 2017-01-21 11:46:26 +08:00
tuple 是 immutable 的，没法重用
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bxb100 OP @czheo list 是临时对象，内存会自动清理， tuple 不会，而且 ()和(1)存放地址区域不同
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HypoChen 2017-01-21 19:20:03 +08:00 1
id(object)
Return the “ identity ” of an object. This is an integer (or long integer) which is guaranteed to be unique and constant for this object during its lifetime. **Two objects with non-overlapping lifetimes may have the same id() value.** ``` >>> id([1]) 4391579520 >>> id([2]) 4391579520 >>> a = [1] >>> b = [1] >>> id([1]) 4391757944 >>> id([2]) 4391757944 >>> id(a) 4391579520 >>> id(b) 4391641672 >>> id([]) 4391757944 ``` |
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